Marta Riu

Effectiveness and safety of colistin for the treatment of multidrug-resistant Pseudomonas aeruginosa infections

Purpose:To describe the clinical and microbiological outcomes of patients infected with multidrug-resistant Pseudomonas aeruginosa (MDRP) treated with colistin (colistimethate sodium) and the adverse events observed with this treatment.Methods:Retrospective study of MDRP infections treated with colistin from 1997 to 2006.Results:121 episodes were identified. The median daily intravenous dose was 240 mg/day; 28.9% of patients received intravenous and nebulized colistin. Clinical outcome was favorable in ten cases of bacteremia (62.5%, n = 16), 43 cases of bronchial infection (72.9%, n = 59), 13 cases of pneumonia (65%, n = 20), 11 cases of urinary infection (84.6%, n = 13), eight cases of skin and soft tissues (72.7%, n = 11), and in the one case of arthritis and one case of otitis. Eradication was achieved in 31 (34.8%) of the 89 patients with available bacteriologic data. Factors associated with bacteriological failure were smoking, chronic obstructive pulmonary disease (COPD), and previous infection with P. aeruginosa. Nephrotoxicity occurred in ten cases (8.3%), with the associated factors being previous chronic renal insufficiency, diabetes mellitus, and aminoglycoside use. Crude mortality was 16.5%, and related MDRP was 12.4%, and was higher in patients with pneumonia or bacteremia (36.1%) than in other types of infections (8.2%).Conclusions:Colistin is a safe option for the treatment of MDRP infections, with acceptable clinical outcomes. However, bacteriological eradication is difficult to achieve, especially in COPD patients.

Eosinophil Count and Neutrophil-Lymphocyte Count Ratio as Prognostic Markers in Patients with Bacteremia: A Retrospective Cohort Study

Introduction There is scarce evidence on the use of eosinophil count as a marker of outcome in patients with infection. The aim of this study was to evaluate whether changes in eosinophil count, as well as the neutrophil-lymphocyte count ratio (NLCR), could be used as clinical markers of outcome in patients with bacteremia. Methods We performed a retrospective study of patients with a first episode of community-acquired or healthcare-related bacteremia during hospital admission between 2004 and 2009. A total of 2,311 patients were included. Cox regression was used to analyze the behaviour of eosinophil count and the NLCR in survivors and non-survivors. Results In the adjusted analysis, the main independent risk factor for mortality was persistence of an eosinophil count below 0.0454·103/uL (HR = 4.20; 95% CI 2.66–6.62). An NLCR value >7 was also an independent risk factor but was of lesser importance. The mean eosinophil count in survivors showed a tendency to increase rapidly and to achieve normal values between the second and third day. In these patients, the NLCR was <7 between the second and third day. Conclusion Both sustained eosinopenia and persistence of an NLCR >7 were independent markers of mortality in patients with bacteremia.

Hospital costs of nosocomial multi-drug resistant Pseudomonas aeruginosa acquisition

BackgroundWe aimed to assess the hospital economic costs of nosocomial multi-drug resistant Pseudomonas aeruginosa acquisition.MethodsA retrospective study of all hospital admissions between January 1, 2005, and December 31, 2006 was carried out in a 420-bed, urban, tertiary-care teaching hospital in Barcelona (Spain). All patients with a first positive clinical culture for P. aeruginosa more than 48 h after admission were included. Patient and hospitalization characteristics were collected from hospital and microbiology laboratory computerized records. According to antibiotic susceptibility, isolates were classified as non-resistant, resistant and multi-drug resistant. Cost estimation was based on a full-costing cost accounting system and on the criteria of clinical Activity-Based Costing methods. Multivariate analyses were performed using generalized linear models of log-transformed costs.ResultsCost estimations were available for 402 nosocomial incident P. aeruginosa positive cultures. Their distribution by antibiotic susceptibility pattern was 37.1% non-resistant, 29.6% resistant and 33.3% multi-drug resistant. The total mean economic cost per admission of patients with multi-drug resistant P. aeruginosa strains was higher than that for non-resistant strains (15,265 vs. 4,933 Euros). In multivariate analysis, resistant and multi-drug resistant strains were independently predictive of an increased hospital total cost in compared with non-resistant strains (the incremental increase in total hospital cost was more than 1.37-fold and 1.77-fold that for non-resistant strains, respectively).ConclusionsP. aeruginosa multi-drug resistance independently predicted higher hospital costs with a more than 70% increase per admission compared with non-resistant strains. Prevention of the nosocomial emergence and spread of antimicrobial resistant microorganisms is essential to limit the strong economic impact.

Risk factors for multidrug-resistant Pseudomonas aeruginosa acquisition. Impact of antibiotic use in a double case-control study

Multidrug-resistant strains of Pseudomonas aeruginosa(MDRPA) have been increasing in some hospitals [1] andmay become a public health problem [2].The emergence of MDRPA has been related to exposureto antibiotics against P. aeruginosa [3, 4]. Most of thesestudies have focussed on particular environments such asthe intensive care unit (ICU) [5] or particular antibioticresistances, mainly quinolone-resistant P. aeruginosa andcarbapenem-resistant P. aeruginosa or specific infectionsites such ventilator-associated pneumonia or bacteraemia[6, 7]. Most studies have used case–control methodology orhave investigated outbreaks, and the case–control studieshave usually compared susceptibility to resistant micro-organisms. This methodology may overestimate the associ-ation between the resistance-defining antibiotic or may befalsely implicated as a potential risk factor for theacquisition of this pattern of susceptibility [8, 9].The aim of this study was to assess the factors related toMDRPA acquisition, especially previous antibiotic expo-sure, using a double case–control methodology [10],analysing all types of infections and all hospital wardsduring a long period of follow-up.We conducted a double case–control epidemiologicalstudy, exploring the risk factors (host characteristics,invasive procedures and, especially, previous antibioticexposure) associated with the acquisition of MDRPA inhospitalised patients from 1 January 2001 to 31 December2006 in a University Hospital with 450 beds. P. aeruginosawas isolated and identified by the microbiology laboratoryby means of routine techniques. The susceptibility of

Importance of appropriateness of empiric antibiotic therapy on clinical outcomes in intra-abdominal infections

OBJECTIVES The objective of this study is to describe the frequency of inappropriate empirical antibiotic therapy in secondary intra-abdominal infection and to identify the possible relationship between inappropriateness and some clinical outcomes. METHODS A retrospective descriptive multicenter study was conducted using hospital secondary databases developed at two university hospitals located in northeast Spain. Participants were patients 18 years of age or older who were diagnosed with community-acquired intra-abdominal infections between January 1, 1998, and December 31, 2000, identified through computerized patient records using ICD-9 codes. Appropriateness of empirical treatment was defined according to the recommendations of the literature. The clinical outcome of each patient was classified as one of the following: (i) resolved with initial therapy, (ii) required second-line antibiotics, (iii) required re-operation, or (iv) in-hospital death. The Fishers exact test or the Chi-squared test for categorical variables and the t-test or Mann-Whitney test for continuous variables were used for comparing groups. Conditional logistic and linear regression analyses were also applied. RESULTS Of 376 cases, 51 cases (13.6 percent, 95 percent confidence interval, 10-17 percent) received inappropriate empirical antibiotic therapy according to the scientific literature. Inappropriate initial empirical treatment was significantly associated with the need for a second line of antibiotics (p < .001), although not with re-operation, mortality, or length of hospitalization. CONCLUSIONS Approximately 14 percent of the patients received inappropriate empirical antibiotic treatment. Worse clinical outcomes consistently were observed in the group of patients receiving inappropriate empirical treatment. The appropriateness of antibiotic treatment for a given infection, in light of the availability of clearly defined clinical guidelines is an easily evaluated aspect of the quality of care.

Design of a score to identify hospitalized patients at risk of drug‐related problems

The potential impact of drug‐related problems (DRP) on morbidity and mortality is a serious concern in hospitalized patients. This study aimed to design a risk score to identify patients most at risk of a DRP.

Bacteriemia comunitaria tratada o identificada de forma ambulatoria tras el alta de un servicio de urgencias

Fundamento y objetivo Los pacientes con bacteriemia suelen requerir ingreso hospitalario, aunque en ocasiones se les remite a su domicilio por diagnostico inapropiado o rapida mejoria. En el presente estudio se describen la evolucion y las intervenciones realizadas en los pacientes con bacteriemia comunitaria remitidos a domicilio. Pacientes y metodo Estudio prospectivo realizado en un hospital de 450 camas desde marzo de 2000 hasta diciembre de 2003. El centro dispone de un equipo que controla todas las bacteriemias. Se identifico a los pacientes enviados a su domicilio desde urgencias y que recibieron tratamiento antimicrobiano inapropiado. Resultados Se diagnostico a 1.172 pacientes con bacteriemia verdadera, de los que 247 (21,1%) fueron remitidos a su domicilio. En 50 casos (20,2%) se considero necesario revaluar al paciente: 36 por tratamiento antibiotico inapropiado, 12 sin tratamiento antibiotico y 2 por falta de informacion. En 34 pacientes (64%) se instauro o modifico el tratamiento antimicrobiano y 10 (20%) requirieron ingreso hospitalario. Excluyendo a los 66 pacientes que fallecieron en las primeras 48 h, la mortalidad bruta de los pacientes remitidos a domicilio fue inferior (4%) a la de los pacientes ingresados (11,9%). Conclusiones Una quinta parte de las bacteriemias comunitarias fueron tratadas de forma ambulatoria. Con frecuencia el tratamiento antibiotico fue inapropiado. Es necesario garantizar un control adecuado de estos pacientes.

Risk adjustment: beyond patient classification systems

UNLABELLED Diagnosis related groups (DRGs) are widely used in several countries. Their various versions aim to value the cost of hospital production. In Europe, the patient classification systems and standard weights used are usually the American originals. OBJECTIVES The objective of this study was to analyse the extent to which DRGs and DRG-weights explain patient cost variability. Different components of patient cost (severity, comorbidities, complications and socioeconomic status), which are not well explained by DRG and which can be approximated by using administrative data, were also analysed. METHODS A total of 35,262 discharges from two public hospitals in Barcelona were analysed. The Health Care Financing Administration (HCFA)-DRGs and the All Patient Refined (APR)- DRGs were calculated. Severity was adjusted by Disease Staging, and comorbidities and complications were calculated using Elixhauser and Charlson comorbidities groupings. An ecological socioeconomic status indicator was used. Linear regressions were estimated to explain per-patient cost variability. RESULTS We found that Medicares DRG-weights explained only 19% of cost variability. Cost-based weights explained nearly 40% (38-42%, depending on the DRG classification used). Exclusion of outliers increased explanatory power to R² = 47-48%. The remaining adjustment variables increased R² to 49-51%. DISCUSSION Medicares DRG-weights are not well-suited to Europe. Cost-based DRG-weights and outlier trimming have significantly greater explanatory power. The remaining clinical and socioeconomic variables have considerably less explanatory power but were statistically significant and behaved as expected. Spanish and other European health authorities should adapt DRG-classification systems to their environments for use in hospital production cost valuation.

Resultados de un proyecto multidisciplinar y multifocal para la disminución de la bacteriemia causada por catéter venoso central, en pacientes no críticos, en un hospital universitario

OBJECTIVE To evaluate a multidisciplinary and multifocal intervention in order to reduce catheter related bloodstream infections (CRBI), based on previously identified risk factors in non-critical patients. METHODS A pre-post-intervention study, 2004-2006. POPULATION patients with a central venous catheter (CVC). The primary endpoint was the CRBI. Other studied variables were patient characteristics, insertion, maintenance and removal of the catheter. The intervention consisted of baseline knowledge and identifying risk factors. In a second period, there was specific training on these identified risk factors and communication of the results, monitoring and evaluation of the CVC inserted. RESULTS We analysed 175 and 200 CVC, respectively. The incidence of CRBI was 15.4% during the pre-intervention and 4.0% in the post-intervention period (P<.001). The incidence of BRC by CVC days in the first group was 8.8 infections 1.000 days of CVC and the second 2,3 (P=.0009). The multivariate analysis found an increased risk of CRBI during the first period (OR 4.32; 95% CI: 1.81-10.29) and the use of total parenteral nutrition (OR: 2.37; 95% CI: 1.10-5. 12). CONCLUSION The application of specific measures directed at all non-critical patients in the entire hospital and involving a large number of professionals has achieved a decrease incidence of 73.9% of CRBI. An acceptable incidence of CRBI was obtained, and, with the completion of the project together with a new awareness, the situation will continue to improve.

Impacto de una intervención de autoevaluación clínica sobre la adecuación de la estancia hospitalaria

Objetivo: Evaluar el impacto de una intervencion sobre la proporcion de estancias inapropiadas (EI), para contrastar la hipotesis de que una intervencion sencilla de informacion y participacion (adeQhos®) permite reducir la proporcion de EI. Metodo: Estudio pre/postintervencion mediante el cuestionario «adeQhos®», que compara 2 grupos experimentales (medicina, cirugia) y 2 grupos control (otras especialidades medicas, cirugia ortopedica y traumatologia), en 10 hospitales de agudos de Cataluna. Los mismos revisores evaluaron la adecuacion mediante el Appropriateness Evaluation Protocol, antes y despues de la intervencion. Resultados: Se revisaron 1.594 estancias antes de la intervencion y 1.495 despues. El 41,1% de todas las estancias revisadas (dia previo al alta) resultaron inapropiadas. La intervencion se realizo sobre 4.613 estancias. Hubo un incremento significativo de EI en el grupo control de medicina (del 39,7 al 48,6%), mientras que en los grupos de intervencion no se observo ninguna disminucion (en medicina del 46,7 al 50,6%, y en cirugia del 27,2 al 31,2%). Sin embargo, la correlacion entre la intensidad de la intervencion y las diferencias de EI antes y despues fue de r = -0,373 (p = 0,106). La intensidad de la intervencion fue desigual en los diferentes hospitales; en los que presentaban una intensidad de intervencion > 60% el porcentaje de EI disminuyo 10,7 puntos en medicina y 4,8 en cirugia, mientras que en los grupos control aumento. Conclusiones: La prevalencia de EI en el dia previo al alta en los hospitales estudiados fue considerablemente alta (del 41,1%). No se observo ninguna reduccion significativa de la inadecuacion hospitalaria tras una intervencion de baja intensidad.